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Used Data (used + data)

Distribution by Scientific Domains
Medical Sciences49%
Life Sciences30%
Humanities and Social Sciences6%
Business, Economics, Finance and Accounting5%
Psychology4%
3 Other Domains6%
Distribution within Medical Sciences
Neurology8%
Consumer Health General4%
25 Other Subdomains72%

Kinds of Used Data

  • i used data
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  • study used data
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    Selected Abstracts

    Metropolitan Open-Space Protection with Uncertain Site Availability

    CONSERVATION BIOLOGY, Issue 2 2005
    ROBERT G. HAIGHT
    acceso público; Chicago; modelo de selección de sitio; optimización; representación de especies Abstract:,Urban planners acquire open space to protect natural areas and provide public access to recreation opportunities. Because of limited budgets and dynamic land markets, acquisitions take place sequentially depending on available funds and sites. To address these planning features, we formulated a two-period site selection model with two objectives: maximize the expected number of species represented in protected sites and maximize the expected number of people with access to protected sites. These objectives were both maximized subject to an upper bound on area protected over two periods. The trade-off between species representation and public access was generated by the weighting method of multiobjective programming. Uncertainty was represented with a set of probabilistic scenarios of site availability in a linear-integer formulation. We used data for 27 rare species in 31 candidate sites in western Lake County, near the city of Chicago, to illustrate the model. Each trade-off curve had a concave shape in which species representation dropped at an increasing rate as public accessibility increased, with the trade-off being smaller at higher levels of the area budget. Several sites were included in optimal solutions regardless of objective function weights, and these core sites had high species richness and public access per unit area. The area protected in period one depended on current site availability and on the probabilities of sites being undeveloped and available in the second period. Although the numerical results are specific for our study, the methodology is general and applicable elsewhere. Resumen:,Planificadores urbanos adquieren espacios abiertos para proteger áreas naturales y proporcionar acceso público a oportunidades de recreación. Debido a presupuestos limitados y a la dinámica de los mercados de terrenos, las adquisiciones se llevan a cabo secuencialmente en función de la disponibilidad de fondos y sitios. Para atender estas características de la planificación, formulamos un modelo de selección de sitios de dos períodos con dos objetivos: maximizar el número esperado de especies representado en sitios protegidos y maximizar el número esperado de personas con acceso a sitios protegidos. Ambos objetivos fueron maximizados con un límite superior en la superficie protegida en los dos períodos. El balance entre la representación de especies y el acceso público fue generado por el método de ponderación de programación de multiobjetivos. La incertidumbre fue representada con un conjunto de escenarios probabilísticos de la disponibilidad de sitios en una formulación lineal-integral. Para demostrar el modelo, utilizamos datos para 27 especies raras en 31 sitios potenciales en el oeste del Condado Lake, cerca de la ciudad de Chicago. Cada curva tenía forma cóncava y la representación de especies descendió a medida que incrementó la accesibilidad pública, con un menor equilibrio en niveles altos del presupuesto para el área. Varios sitios fueron incluidos en soluciones óptimas independientemente de las funciones de ponderación de los objetivos, y estos sitios tuvieron alta riqueza de especies y acceso público por unidad de área. La superficie protegida en el período uno dependió de la disponibilidad de sitios y de las probabilidades de que los sitios no fueran desarrollados y de su disponibilidad en el segundo período. Aunque los resultados numéricos son específicos a nuestro estudio, la metodología es general y aplicable en otros sitios. [source]

    Synergistic Effects of Subsistence Hunting and Habitat Fragmentation on Amazonian Forest Vertebrates

    CONSERVATION BIOLOGY, Issue 6 2001
    Carlos A. Peres
    These effects are likely to be considerably aggravated by forest fragmentation because fragments are more accessible to hunters, allow no (or very low rates of ,) recolonization from nonharvested source populations, and may provide a lower-quality resource base for the frugivore-granivore vertebrate fauna. I examined the likelihood of midsized to large-bodied bird and mammal populations persisting in Amazonian forest fragments of variable sizes whenever they continue to be harvested by subsistence hunters in the aftermath of isolation. I used data from a comprehensive compilation of game-harvest studies throughout Neotropical forests to estimate the degree to which different species and populations have been overharvested and then calculated the range of minimum forest areas required to maintain a sustainable harvest. The size distribution of 5564 Amazonian forest fragments,estimated from Landsat images of six regions of southern and eastern Brazilian Amazonia,clearly shows that these are predominantly small and rarely exceed 10 ha, suggesting that persistent overhunting is likely to drive most midsized to large vertebrate populations to local extinction in fragmented forest landscapes. Although experimental studies on this negative synergism remain largely unavailable, the prospect that increasingly fragmented Neotropical forest regions can retain their full assemblages of avian and mammalian species is unlikely. Resumen: La cacería de subsistencia tiene efectos negativos profundos sobre la diversidad de especies, la biomasa y estructura de las comunidades de vertebrados en bosques de la Amazonía que de otra forma están poco perturbadas. Estos efectos se agravan considerablemente por la fragmentación del bosque porque los fragmentos son más accesibles a los cazadores, no permiten la recolonización por poblaciones no cazadas o disminuyen las tasas de recolonizacíon y pueden proporcionar una base de recursos de menor calidad para la fauna de vertebrados frugívoro-granívoros. Examiné la posibilidad de persistencia de poblaciones de aves y mamíferos medianos a grandes en fragmentos de bosque de tamaño variable si continúan sujetos a la cacería de subsistencia como una consecuencia del aislamiento. Utilicé datos de una compilación extensiva de estudios de cacería en bosques neotropicales para estimar el grado en que diferentes especies y poblaciones han sido sobre explotadas y calculé el área de bosque minima requerida para mantener una cosecha sostensible. La distribucíon de tamaños de 5564 fragmentos de bosque amazónica, estimado a partir de imágues de Landsat de seis regiones del sur y del esté de la Amazonía brasileña indica claramente que estos fragmentós son principalmente pegueños y que rara vez exceden las lolta, lo que sugiere que la sobre cacería persistente probablemente lleve a la extincíon local de poblaciones de vertebrados de tamaño mediano a grande en paisajes boscosos fragmentados. Aunque estudios experimentales de este sinergismo negativo no están disponibles, la perspectiva de que las regiones neotropicales cada vez más fragmentadas, puedan retener las comunidades completas de aves y mamíferos poco es probable. [source]

    Non-remission of depression in the general population as assessed by the HAMD-7 scale

    DEPRESSION AND ANXIETY, Issue 5 2008
    Andrew G. Bulloch Ph.D.
    Abstract Remission from the symptoms of depression is the optimal outcome for depression treatment. Many studies have assessed the frequency of treatment, but there are none that have estimated the frequency of treated remission in the general population. We addressed this issue in the population of Alberta using a brief Hamilton Depression Rating Scale (HAMD)-7 scale (recently validated against the HAMD-17 scale in a clinical setting) that has been proposed as a suitable indicator for remission in primary care. We used data from a survey conducted within the Alberta Depression Initiative in 2005 (n=3,345 adults), to produce a population-based estimate of the number of respondents taking antidepressant medication for depression. From this group we selected a subpopulation that did not screen positive when the MINI module for major depression was administered (i.e., who did not have an active episode). Non-remission in this subpopulation was assessed with a version of the HAMD-7 scale adapted for telephone administration by a nonclinician. Of the survey respondents, 189 reported taking antidepressant medication for depression. Of these, 115 were found not to have an active episode. However, 49.0% of this subpopulation was not in remission as evaluated by the HAMD-7. We estimate that 1.3% (95% confidence interval, 0.9,2.0%) of the population is in treated non-remission for depression. Our study indicates a substantial degree of non-remission from depression in individuals taking antidepressants in the general population. This suggests that, in addition to increasing the frequency of treatment, increasing the effectiveness of treatment can have an impact on population health. Depression and Anxiety 0:1,5, 2007. © 2007 Wiley-Liss, Inc. [source]

    Side-effects of antipsychotic medication and health-related quality of life in schizophrenia

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 2009
    P. E. Bebbington
    Objective:, This analysis used data from the large (n = 1208) European Schizophrenia Cohort to examine the association between subjective side-effects of antipsychotic medication and the Mental and Physical Composite Scores (MCS; PCS) of the SF-36 scale. Method:, Relationships between the subjective evaluation of side-effects identified from the Subjective Side-Effects Scale and the adjusted mean score on the PCS and MCS were examined. Where appropriate, these associations of subjective side-effects were compared with those of the same side-effects measured objectively. Results:, In this study, subjective side-effects of antipsychotic medication were linked either to both the PCS and the MCS or, in a few instances, to neither. Subjective evaluations of sexual side-effects were associated only with the MCS, those of sialorrhoea only with the PCS. Objective ratings of extrapyramidal side-effects were related neither to PCS nor to MCS. Conclusion:, These data suggest that side-effects, whether subjective or objective, may need to be considered individually in relation to their impact on quality of life. [source]

    Changes in serum leptin concentrations in overweight Japanese men after exercise

    DIABETES OBESITY & METABOLISM, Issue 5 2004
    N. Miyatake
    Aim:, To investigate the link between serum leptin concentrations and exercise. Design:, Cross-sectional and longitudinal studies of an exercise intervention. Subjects:, 110 Japanese overweight men aged 32,59 years were recruited. At baseline, the average body mass index (BMI) was 28.5 ± 2.5 kg/m2. From this group, we used data of 36 overweight men (BMI, 28.9 ± 2.3) for a 1-year exercise programme. Measurements:, Leptin was measured at baseline and after 1 year. Fat distribution was evaluated by visceral fat (V) and subcutaneous fat (S) areas measured with computed tomography (CT) scanning at umbilical levels. Anthropometric parameters, aerobic exercise level, muscle strength and flexibility were also investigated at baseline and after 1 year. Results:, In the first analysis, using cross-sectional data, leptin was significantly correlated with total body fat (r = 0.760, p < 0.01), V (r = 0.383, p < 0.01) and S (r = 0.617, p < 0.01) areas. In the second analysis, using longitudinal data, leptin was significantly reduced after 1 year (pre 6.7 ± 4.0 ng/ml vs. post 5.1 ± 3.1 ng/ml, p < 0.01). Results showed that steps per day were increased, and aerobic exercise level, weight-bearing index (WBI) and insulin resistance were significantly improved. Although, there was a positive correlation between , leptin(positive changes in leptin after 1 year) and anthropometric measurements such as , body weight, , BMI and , body fat, leptin/body weight, leptin/BMI and leptin/body fat ratios were significantly reduced during exercise intervention. Conclusion:, The present study indicated exercise significantly lowers serum leptin concentrations, and thus it may improve the leptin resistance observed in overweight Japanese men. [source]

    The transferability of distribution models across regions: an amphibian case study

    DIVERSITY AND DISTRIBUTIONS, Issue 3 2009
    Flavio Zanini
    ABSTRACT Aim, Predicting species distribution is of fundamental importance for ecology and conservation. However, distribution models are usually established for only one region and it is unknown whether they can be transferred to other geographical regions. We studied the distribution of six amphibian species in five regions to address the question of whether the effect of landscape variables varied among regions. We analysed the effect of 10 variables extracted in six concentric buffers (from 100 m to 3 km) describing landscape composition around breeding ponds at different spatial scales. We used data on the occurrence of amphibian species in a total of 655 breeding ponds. We accounted for proximity to neighbouring populations by including a connectivity index to our models. We used logistic regression and information-theoretic model selection to evaluate candidate models for each species. Location, Switzerland. Results, The explained deviance of each species' best models varied between 5% and 32%. Models that included interactions between a region and a landscape variable were always included in the most parsimonious models. For all species, models including region-by-landscape interactions had similar support (Akaike weights) as models that did not include interaction terms. The spatial scale at which landscape variables affected species distribution varied from 100 m to 1000 m, which was in agreement with several recent studies suggesting that land use far away from the ponds can affect pond occupancy. Main conclusions, Different species are affected by different landscape variables at different spatial scales and these effects may vary geographically, resulting in a generally low transferability of distribution models across regions. We also found that connectivity seems generally more important than landscape variables. This suggests that metapopulation processes may play a more important role in species distribution than habitat characteristics. [source]

    Why are ferns regularly over-represented on state and provincial rare plant lists?

    DIVERSITY AND DISTRIBUTIONS, Issue 6 2006
    Matthew Wild
    ABSTRACT Several recent studies have suggested that rare species are not randomly distributed throughout plant taxa. This would appear to apply to North American ferns, which are frequently over-represented on local lists of rare plant species. However, such lists often paint a skewed portrait of the true situation because of our tendency to recognize the rarity of well-known and charismatic species while ignoring that of lesser-known or less-appreciated species. In order to verify if this over-representation of ferns is a real and consistent trend throughout local floras in North America, we used data from what we consider to be the most complete and objective available database: NatureServe Explorer (http://www.natureserve.org/explorer/). We compiled data on total vascular plant species, total fern species, as well as rare vascular plant species and rare fern species for each North American subnational (Canadian province or US state) flora. Rare species were defined as those belonging to one of NatureServe's ,at risk' categories. The null hypothesis that the contribution of rare ferns to total rare species did not differ from their contribution to the total vascular flora was assessed using ,2. Out of 64 subnational floras, we obtained significantly higher values than expected in 28 cases, and significantly lower in only one case. Similar trends hold true for individual fern families. These tendencies could be related to several factors of anthropogenic, biological, climatological, evolutionary, and geographical origin. However, we believe that the main reason is related to scale, namely the geopolitical units at which rarity is often studied. Our results illustrate one of the problems of a parochial approach to conservation, where the perceived rarity of an entire taxon is exaggerated because of the scale at which rarity is addressed. [source]

    An ecological law and its macroecological consequences as revealed by studies of relationships between host densities and parasite prevalence

    ECOGRAPHY, Issue 3 2001
    Per ArnebergArticle first published online: 30 JUN 200
    Epidemiological models predict a positive relationship between host population density and abundance of macroparasites. Here I test these by a comparative study. I used data on communities of four groups of parasites inhabiting the gastrointestinal tract of mammals, nematodes of the orders Oxyurida, Ascarida, Enoplida and Spirurida, respectively. The data came from 44 mammalian species and represent examination of 16 886 individual hosts. I studied average prevalence of all nematodes within an order in a host species, a measure of community level abundance, and considered the potential confounding effects of host body weight, fecundity, age at maturity and diet. Host population density was positively correlated with parasite prevalence within the order Oxyurida, where all species have direct life cycles. Considering the effects of other variables did not change this. This supports the assumption that parasite transmission rate generally is a positive function of host population density. It also strengthens the hypothesis that host densities generally act as important determinants of species richness among directly transmitted parasites and suggests that negative influence of such parasites on host population growth rate increase with increasing host population density among host species. Within the other three nematode orders, where a substantial number of the species have indirect life cycles, no relationships between prevalence and host population density were seen. Again, considering the effects of other variables did not affect this conclusion. This suggests that host population density is a poor predictor of species richness of indirectly transmitted parasites and that effects of such parasites on host population dynamics do not scale with host densities among species of hosts. [source]

    Body size and host range in European Heteroptera

    ECOGRAPHY, Issue 1 2000
    Martin Brändle
    We used data on body size and host range of phytophagous Heteroptera in central Europe, an inverse measure of specialisation, to analyse the relationship of body size vs specialisation: 1) we found a clear positive relationship between body size and host range using species as independent data points. 2) However, a nested analysis of variance shows that most of the variance in body size occurred at higher taxonomic levels whereas most of the variance in host specialisation occurred between species. This suggests different phylogenetic inertia of body size and specialisation. Nevertheless, using means of different higher taxonomic levels there is still a significant positive correlation between body size and host range. 3) With more sophisticated methods of correcting for the phylogenetic relatedness between species, the positive correlation between body size and host range still holds, despite the different assumptions of each method. Thus, the relationship between body size and host range is a very robust pattern in true bugs. [source]

    No evidence that sexual selection is an ,engine of speciation' in birds

    ECOLOGY LETTERS, Issue 3 2003
    Edward H. Morrow
    Abstract Sexual selection has been implicated as having a role in promoting speciation, as it should increase the rate of evolution of reproductive isolation, and there is some comparative evidence that sexual selection may be related to imbalances in clade size seen in resolved phylogenies. By employing a new comparative method we are able to investigate the role of sexual selection in explaining the patterns of species richness across birds. We used data for testes size as an index of post-mating sexual selection, and sexual size dimorphism and sexual dichromatism as indices of pre-mating sexual selection. These measures were obtained for 1031 species representing 467 genera. None of the variables investigated explained the patterns of species richness. As sexual selection may also increase extinction rates, the net effect on species richness in any given clade will depend on the balancing effects of sexual selection upon speciation and extinction rates. We suggest that variance across clades in this balance may have resulted in the lack of a relationship between species richness and sexual selection seen in birds. [source]

    Missing data assumptions and methods in a smoking cessation study

    ADDICTION, Issue 3 2010
    Sunni A. Barnes
    ABSTRACT Aim A sizable percentage of subjects do not respond to follow-up attempts in smoking cessation studies. The usual procedure in the smoking cessation literature is to assume that non-respondents have resumed smoking. This study used data from a study with a high follow-up rate to assess the degree of bias that may be caused by different methods of imputing missing data. Design and methods Based on a large data set with very little missing follow-up information at 12 months, a simulation study was undertaken to compare and contrast missing data imputation methods (assuming smoking, propensity score matching and optimal matching) under various assumptions as to how the missing data arose (randomly generated missing values, increased non-response from smokers and a hybrid of the two). Findings Missing data imputation methods all resulted in some degree of bias which increased with the amount of missing data. Conclusion None of the missing data imputation methods currently available can compensate for bias when there are substantial amounts of missing data. [source]

    Early weaning and alcohol disorders in offspring: biological effect, mediating factors or residual confounding?

    ADDICTION, Issue 8 2009
    Rosa Alati
    ABSTRACT Aims This study explores associations between early weaning and alcohol use disorders in youth and mechanisms by which these associations may operate. Design We used data from the Mater University Study of Pregnancy and its outcomes, an Australian birth cohort study based in Brisbane. Setting and participants: This study is based on a subsample of 2370 participants for whom complete data were available at age 21 years. Length and method of breastfeeding were assessed at 6 months. Measurements Alcohol use disorders were assessed at age 21 using the life-time version of the Composite International Diagnostic Interview,computerized version (CIDI-Auto). We adjusted for maternal age, marital status, education, alcohol, tobacco use, anxiety, depression and maternal attitudes towards the baby. Attention Deficit and Hyperactivity Disorders (ADHD) and Intellect Quotient (IQ) were measured with the Child Behaviour Checklist (5 years) and the Ravens SM (14 years), respectively. Findings Those who had been weaned within 2 weeks of being born and breastfed at regular intervals were at increased risk of meeting criteria for alcohol use disorders at age 21 [odds ratio (OR) 1.71, 95% confidence interval (CI):1.07, 2.72]. Conclusion This study confirms a small but robust association between early weaning and increased risk of alcohol use disorders. [source]

    Hospitalizations for opioid poisoning: a nation-wide population-based study in Denmark, 1998,2004

    ADDICTION, Issue 1 2009
    Anne-Mette Bay Bjørn
    ABSTRACT Aims To assess hospitalization rates (HR) for poisoning with heroin, methadone or strong analgesics and relate them to quantities of prescribed methadone and strong analgesics in Denmark between 1998 and 2004. Design Population-based ecological study. Settings We extracted data on all emergency department visits and hospital admissions registered in the Danish National Patient Registry with a diagnosis of poisoning with heroin (n = 1688), methadone (n = 173) or strong analgesics (n = 384). To ascertain sale of prescribed medications we used data from the Danish Medicines Agency. Measurements Age- and gender-standardized HR and defined daily doses (DDD) per 1000 people per day. Findings HR for heroin poisoning was 4.4 [95% confidence interval (CI): 3.8,4.9] per 100 000 person-years (p-y) in 1998 and 4.6 (CI: 4.0,5.2) per 100 000 p-y in 2004. HR for methadone poisoning increased from 0.1 (CI: 0.0,0.2) per 100 000 p-y in 1998 to 1.1 (CI: 0.8,1.4) per 100 000 p-y in 2004. HR for poisoning with strong analgesics increased from 0.6 (CI: 0.4,0.9) per 100 000 p-y in 1998 to 2.1 (CI: 1.8,2.6) per 100 000 p-y in 2004. The sale of prescribed strong analgesics (5.0 DDD per 1000 people per day in 1998 to 5.9 DDD in 2004) and methadone (3.0 DDD per 1000 people per day in 1998 to 3.4 DDD in 2004) increased slightly between 1998 and 2004. Conclusion Increasing sale of prescribed methadone and strong analgesics coincided with increasing HRs of poisoning with these drugs, whereas HR of heroin poisoning varied. Further longitudinal studies are important for the guidance of future policy making. [source]

    Coxibs: evolution of prescription's behaviour in France

    FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2007
    Julie Biga
    Abstract The aim of the present study was, first to characterize profiles of coxibs' prescribers [general practitioners (GPs) and rheumatologists] in 2002 in France and, secondly, to identify factors associated with modification of this profile 1 year later. All GPs and rheumatologists from Midi-Pyrenees, Aquitaine, Languedoc-Roussillon and Pays de Loire areas (South of France: 11 050 000 inhabitants) were included in the study. For each practitioner, we used data concerning all non-steroidal anti-inflammatory drugs (NSAIDs) including coxibs reimbursed during period 1 (P1; January,March 2002) and period 2 (P2; January,March 2003). The ratio between the number of coxibs' prescriptions and the total number of NSAIDs' prescriptions (including coxibs) was used to define the two profiles of prescribers, one with a low level of coxibs' prescriptions and another one with a high level of coxibs' prescriptions. Characteristics of practitioners and characteristics of their practices were compared according to this profile. In the second step, we investigated the characteristics (of practitioners and practices) associated with an increase in the level of coxibs' prescriptions in P2 for practitioners with a low level of coxibs' prescriptions in P1. Results are expressed as odds ratio with their 95% confidence intervals. A positive statistical link was found between a high level of coxibs' prescriptions, the speciality of rheumatologist or extra costs for consultation. In contrast, a negative association was observed with female gender or age below 44 years. No relationship was found with the status of referent. Concerning practices' characteristics of practitioners, there was a positive statistical link between a high ratio of coxibs' prescriptions and high co-prescriptions of gastroprotective agents and a negative association with a high number of acts, a high proportion of patients with chronic disabling diseases (CDD) or a high number of patients between 15 and 64 years. There was no statistical link with proportion of patients covered by Universal Medical Coverage (UMC) or aged more than 65 years. Among the factors involved in the increase in the ratio (between P1 and P2), no relationship was found with practitioners' characteristics. In contrast, some factors related to practices (level of gastroprotective co-prescriptions, number of acts, number of CDD patients) were related to a change in coxibs' prescriptions between P1 and P2. This study allowed to discuss some relationships between coxibs' prescription and practitioners' (age, gender, medical speciality or extra costs for consultation) or practices' (level of medical practice, patients' age, number of CDD patients or level of gastroprotective prescriptions) characteristics. In contrast, some other factors like the referent status or the number of patients with UMC are not related. Physicians, initially low prescribers of coxibs and increasing their coxibs' prescriptions during the period of our study, were those with a high level of gastroprotective prescriptions, a low number of acts or a small proportion of CDD patients. [source]

    Genotyping errors, pedigree errors, and missing data

    GENETIC EPIDEMIOLOGY, Issue S1 2005
    Anthony L. Hinrichs
    Abstract Our group studied the effects of genotyping errors, pedigree errors, and missing data on a wide range of techniques, with a focus on the role of single-nucleotide polymorphisms (SNPs). Half of our group used simulated data, and half of our group used data from the Collaborative Study on the Genetics of Alcoholism (COGA). The simulated data had no missing genotypes and no genotyping errors, so our group, as a whole, removed data and introduced artificial errors to study the robustness of various techniques. Our teams showed that genotyping errors are less detectable and may have a greater impact on SNPs than on microsatellites, but recently developed methods that account for genotyping errors help reduce false positives, and the assumptions of these methods appear to be supported by observations from repeated genotyping. The ability to detect linkage disequilibrium (LD) was also substantially reduced by missing data; this in turn could affect tagging SNPs chosen to generate haplotypes. In the COGA sample, genotyping measurements were repeated in three ways. First, full-genome screens were performed on three sets of markers: 328 microsatellites, 11,560 SNPs from the Affymetrix GeneChip Mapping 10,K Array marker set, and 4,720 SNPs from the Illumina Linkage III panel. Second, the entire Affymetrix marker set was typed on the same 184 individuals by two different laboratories. Finally, the Affymetrix and Illumina marker panels had 94 SNPs in common. Our teams showed that both SNPs and microsatellites can be readily used to identify pedigree errors, and that SNPs have fewer genotyping errors and a low inconsistency rate. However, a fairly high rate of no-calls, especially for the Affymetrix platform, suggests that the inconsistency rate may be higher than observed. Genet. Epidemiol. 29(Suppl. 1):S120,S124, 2005. © 2005 Wiley-Liss, Inc. [source]

    Thickness of the lithosphere east of the Dead Sea Transform

    GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2006
    Ayman Mohsen
    SUMMARY We use the S receiver function method to study the lithosphere at the Dead Sea Transform (DST). A temporary network of 22 seismic broad-band stations was operated on both sides of the DST from 2000 to 2001 as part of the DESERT project. We also used data from six additional permanent broad-band seismic stations at the DST and in the surrounding area, that is, in Turkey, Saudi Arabia, Egypt and Cyprus. Clear S -to- P converted phases from the crust,mantle boundary (Moho) and a deeper discontinuity, which we interpret as lithosphere,asthenosphere boundary (LAB) have been observed. The Moho depth (30,38 km) obtained from S receiver functions agrees well with the results from P receiver functions and other geophysical data. We observe thinning of the lithosphere on the eastern side of the DST from 80 km in the north of the Dead Sea to about 65 km at the Gulf of Aqaba. On the western side of the DST, the few data indicate a thin LAB of about 65 km. For comparison, we found a 90-km-thick lithosphere in eastern Turkey and a 160-km-thick lithosphere under the Arabian shield, respectively. These observations support previous suggestions, based on xenolith data, heat flow observations, regional uplift history and geodynamic modelling, that the lithosphere around DST has been significantly thinned in the Late Cenozoic, likely following rifting and spreading of the Red Sea. [source]

    Changes in topsoil carbon stock in the Tibetan grasslands between the 1980s and 2004

    GLOBAL CHANGE BIOLOGY, Issue 11 2009
    YUANHE YANG
    Abstract Climate warming is likely inducing carbon loss from soils of northern ecosystems, but little evidence comes from large-scale observations. Here we used data from a repeated soil survey and remote sensing vegetation index to explore changes in soil organic carbon (SOC) stock on the Tibetan Plateau during the past two decades. Our results showed that SOC stock in the top 30 cm depth in alpine grasslands on the plateau amounted to 4.4 Pg C (1 Pg=1015 g), with an overall average of 3.9 kg C m,2. SOC changes during 1980s,2004 were estimated at ,0.6 g C m,2 yr,1, ranging from ,36.5 to 35.8 g C m,2 yr,1 at 95% confidence, indicating that SOC stock in the Tibetan alpine grasslands remained relatively stable over the sampling periods. Our findings are nonconsistent with previous reports of loss of soil C in grassland ecosystems due to the accelerated decomposition with warming. In the case of the alpine grasslands on the Tibetan Plateau studied here, we speculate that increased rates of decomposition as soils warmed during the last two decades may have been compensated by increased soil C inputs due to increased grass productivity. These results suggest that soil C stock in terrestrial ecosystems may respond differently to climate change depending on ecosystem type, regional climate pattern, and intensity of human disturbance. [source]

    Climate change effects on upland stream macroinvertebrates over a 25-year period

    GLOBAL CHANGE BIOLOGY, Issue 5 2007
    ISABELLE DURANCE
    Abstract Climate change effects on some ecosystems are still poorly known, particularly where they interact with other climatic phenomena or stressors. We used data spanning 25 years (1981,2005) from temperate headwaters at Llyn Brianne (UK) to test three hypotheses: (1) stream macroinvertebrates vary with winter climate; (2) ecological effects attributable to directional climate change and the North Atlantic Oscillation (NAO) are distinguishable and (3) climatic effects on macroinvertebrates depend on whether streams are impacted by acidification. Positive (i.e. warmer, wetter) NAO phases were accompanied by reduced interannual stability (=similarity) in macroinvertebrate assemblage in all streams, but associated variations in composition occurred only in acid moorland. The NAO and directional climate change together explained 70% of interannual variation in temperature, but forest and moorland streams warmed respectively by 1.4 and 1.7°C (P<0.001) between 1981 and 2005 after accounting for NAO effects. Significant responses among macroinvertebrates were confined to circumneutral streams, where future thermal projections (+1, +2, +3°C) suggested considerable change. Spring macroinvertebrate abundance might decline by 21% for every 1°C rise. Although many core species could persist if temperature gain reached 3°C, 4,10 mostly scarce taxa (5,12% of the species pool) would risk local extinction. Temperature increase in Wales approaches this magnitude by the 2050s under the Hadley HadCM3 scenarios. These results support all three hypotheses and illustrate how headwater stream ecosystems are sensitive to climate change. Altered composition and abundance could affect conservation and ecological function, with the NAO compounding climate change effects during positive phases. We suggest that acidification, in impacted streams, overrides climatic effects on macroinvertebrates by simplifying assemblages and reducing richness. Climatic processes might, nevertheless, exacerbate acidification or offset biological recovery. [source]

    Why does the unimodal species richness,productivity relationship not apply to woody species: a lack of clonality or a legacy of tropical evolutionary history?

    GLOBAL ECOLOGY, Issue 3 2008
    Lauri Laanisto
    ABSTRACT Aim, To study how differences in species richness patterns of woody and herbaceous plants may be influenced by ecological and evolutionary factors. Unimodal species richness,productivity relationships (SRPRs) have been of interest to ecologists since they were first described three decades ago for British herbaceous vegetation by J. P. Grime. The decrease in richness at high productivity may be due to competitive exclusion of subordinate species, or diverse factors related to evolution and dispersal. Unimodal SRPRs are most often reported for plants, but there are exceptions. For example, unimodal SRPRs are common in the temperate zone but not in the tropics. Similarly, woody species and forest communities in the Northern Hemisphere do not tend to show unimodal SRPRs. Location, Global. Methods, We used data from the literature to test whether a unimodal SRPR applies to woody species and forest communities on a global scale. We explored whether the shape of SRPRs may be related to the lack of clonality in woody species (which may prevent their being competitively superior), or the legacy of evolutionary history (most temperate woody species originate from tropical lineages, and due to niche conservatism they may still demonstrate ,tropical patterns'). We used case studies that reported the names of the dominant or most abundant species for productive sites. Results, Woody species were indeed less clonal than herbaceous species. Both clonality and the temperate evolutionary background of dominating species were associated with unimodality in SRPRs, with woodiness modifying the clonality effect. Main conclusions, The unimodal SRPR has been common in the ecological literature because most such studies originate from temperate herbaceous communities with many clonal species. Consequently, both evolutionary and ecological factors may influence species richness patterns. [source]

    Variation in litterfall-climate relationships between coniferous and broadleaf forests in Eurasia

    GLOBAL ECOLOGY, Issue 2 2004
    Chunjiang Liu
    ABSTRACT Aim, The objectives of this study were to determine the relationships between climatic factors and litterfall in coniferous and broadleaf forests in Eurasia and to explore the difference in litterfall between coniferous and broadleaf forests as related to climate at a continental scale. Location, We have used data from across Eurasia. Methods, The relationships between litterfall and climatic factors were examined using linear regression analysis of a compilation of published data from coniferous and broadleaf forests in Eurasia. Results, The relationships between litterfall and climatic factors show that in the temperate, subtropical, and tropical areas, broadleaf forests had higher litterfall than coniferous ones, whilst the opposite was found for boreal forests. Combining all climatic zones, a multiple regression analysis using annual mean temperature (T) and annual precipitation (P) as independent variables gave an adjusted R2 () of 0.272 for total litterfall in coniferous forests (n = 199, P < 0.001), 0.498 for broadleaf litterfall (n = 240, P < 0.001), and 0.535 for combined coniferous and broadleaf litterfall (n = 439, P < 0.001). The linear models for broadleaf stands have significantly higher coefficients for T and P than those for coniferous ones but the intercepts were similar. Thus, litterfall in broadleaf forests increased faster with T and P than that in coniferous forests. Further, a transformation of temperature and precipitation to relative units showed that a relative-unit change in T had a larger impact than P on total litterfall in broadleaf forests. The results indicate that at a continental scale, climatic controls over litterfall differ between coniferous and broadleaf forests. Conclusions, A relative unit change in annual mean temperature has a greater effect on litterfall compared to the same change in annual precipitation across the Eurasian forests. Further, the higher response to T for broadleaf forests indicates a difference in climate control between coniferous and broadleaf forests at a continental scale, and consequently different litterfall responses to climate change. [source]

    FEIBA® in treatment of acute bleeding episodes in patients with haemophilia A and factor VIII inhibitors: a retrospective survey in regional haemophilia centre

    HAEMOPHILIA, Issue 3 2009
    P. SMEJKAL
    Summary., FEIBA® (factor eight inhibitor by-passing activity) is used to achieve haemostasis in haemophiliacs with inhibitor. The aim of this study was to evaluate efficacy and consumption of the product in treatment of haemorrhages in haemophiliacs with factor VIII inhibitor, and determine factors that can influence the results of treatment. We used data from our haemophilia centre from years 2000,2008. Six haemophiliacs with factor VIII inhibitor were treated on demand with FEIBA® for 61 bleeding episodes (45 haemarthroses, six muscle bleeds, six other sites bleeds and four multiple sites bleeds). The median cumulative dose of FEIBA® per bleeding episode was 205 U kg,1. Bleeding was stopped in 96.7% (59 of 61) of events but re-bleeding occurred in 3 events (4.9%) within 48 h after cessation of bleeding. In home treatment (20 of 61) bleeding stopped in 90% (18 of 20) without recurrence and the median consumption per event was reduced to 153 U kg,1. Without the use of home treatment the median consumption was 250 U kg,1 per event and bleeding ceased definitely in 92.7% (38 of 41) of cases. The cumulative dose of FEIBA® was lower for three episodes with re-bleeding: median 96 U kg,1 but not in the two cases of ineffective treatment: 361 U kg,1. FEIBA® in management of bleeding episodes completely resolved the haemorrhage in 91.8% of events and in a further 4.9% if treatment was restarted. Using home treatment saved expenditure due to the lower cumulative dose needed for treatment of haemorrhage. [source]

    Perceptions about quality of life in a school-based population of adolescents with menorrhagia: implications for adolescents with bleeding disorders

    HAEMOPHILIA, Issue 3 2008
    A. PAWAR
    Summary., This study examined the effect of menorrhagia on the quality of life (QOL) of adolescents. We used data from a survey of 45 adolescents. Using the Pictorial Blood Assessment Chart (PBAC) and a PBAC score of ,100 we identified adolescents likely to have menorrhagia. Our statistical analysis indicated that menorrhagia adversely affects the QOL of adolescents. In this article we discuss the implications of our study and future research avenues. [source]

    Cost savings in migraine associated with less chest pain on new triptan therapy.

    HEADACHE, Issue 3 2003
    JT Wang
    Am J Manag Care. 2002 Feb;8(3 Suppl):S102-S107 Objectives: This article constructs an economic model to estimate cost of chest-pain-related care in migraine patients receiving almotriptan 12.5 mg compared with those receiving sumatriptan 50 mg. Study Design: This population-based, retrospective cohort study used data from the MEDSTAT Marketscan database (Ann Arbor, Michigan) to quantify incidence and costs of chest-pain-related diagnoses and procedures. After a 6-month exclusion period, the study used a pre-post design, with baseline and treatment periods defined, respectively, as 5 months before and after receiving sumatriptan therapy. An economic model was constructed to estimate annual cost savings per 1,000 patients receiving almotriptan instead of sumatriptan as a function of differing rates of chest pain. Annual direct medical cost avoided was calculated for a hypothetical health plan covering 1 million lives. Results: Among a cohort of 1,390 patients, the incidence of chest-pain-related diagnoses increased significantly (43.6%) with sumatriptan, from 110 during the baseline period to 158 during the treatment period (P = .003). Aggregate costs for chest-pain-related diagnoses and procedures increased 33.1%, from $22,713 to $30,234. Payments for inpatient hospital services rose 10-fold; costs for primary care visits and outpatient hospital visits rose 53.1% and 14.4%, respectively. Payments for angiography increased from $0 to $462, and costs for chest radiographs and electrocardiograms increased 58.7% and 31.2%, respectively. Sumatriptan treatment was associated with a 3-fold increase in payments for services for painful respiration and other chest pain. The model predicted $11,215 in direct medical cost savings annually per 1000 patients treated with almotriptan instead of sumatriptan. Annual direct medical costs avoided for the health plan totaled $195,913. Conclusion: Using almotriptan instead of sumatriptan will likely reduce the cost of chest-pain-related care for patients with migraine headaches. Comment: In my view, this study takes conjecture a step too far. The lower reported chest adverse events (AEs) reported in clinical trials where all AEs are scrutinized will not necessarily lead to lower reporting in the clinic. This hypothesis remains to be proven in a well-designed post-marketing surveillance program, untarnished by commercial sponsorship. Until such an independent prospective study is carried out, the extrapolations described here and in similar papers are pure conjecture and should be classed as the lowest grade of evidence on a par with uncorroborated clinical opinion. DSM [source]

    Almotriptan Reduces the Incidence of Migraine-Associated Symptoms: A Pooled Analysis

    HEADACHE, Issue 2002
    Roger Cady MD
    Objectives.,Evaluate the reduction in migraine-associated symptoms after administration of a single oral dose of almotriptan. Methods.,This pooled analysis (N=1773) used data from three randomized, placebo-controlled, phase III trials (studies A, B, and C) to determine the incidence of migraine-associated symptoms (defined as nausea, vomiting, photophobia, and phonophobia) 2 hours after a single oral dose of study medication (almotriptan, sumatriptan, or placebo). Outcome data was extracted from studies A and B for placebo and the almotriptan 6.25-mg and 12.5-mg groups, and from study C for placebo, almotriptan 12.5-mg, and sumatriptan 100-mg groups. Results.,The incidence of nausea, photophobia, and phonophobia at 2 hours after dosing with study medication was significantly reduced (all P < .05) with almotriptan 6.25 mg or 12.5 mg compared with placebo. The percentage of patients with vomiting was lower with both doses of almotriptan in studies A and B compared with placebo, although differences were significant only for the 6.25-mg dose in study A (P < .001). For study C, the incidence of nausea, vomiting, photophobia, and phonophobia was similar for almotriptan and sumatriptan and lower than with placebo at 2 hours after dosing. Significant reductions (all P < .05) versus placebo were observed in the incidence of vomiting and phonophobia with almotriptan 12.5 mg, and photophobia and phonophobia with sumatriptan 100 mg. Conclusion.,Almotriptan provides relief from migraine-associated symptoms of nausea, vomiting, photophobia, and phonophobia, and thus represents an attractive treatment option for a wide spectrum of migraine symptomatology. [source]

    Almotriptan Increases Pain-Free Status in Patients With Acute Migraine Treated in Placebo-Controlled Clinical Trials

    HEADACHE, Issue 2002
    FRCP(C), Ninan T. Mathew MD
    Objectives.,Evaluate the efficacy of a single oral dose of almotriptan in achieving pain-free status during treatment of acute migraine attacks. Methods.,This pooled analysis (N=1321) used data from two randomized, placebo-controlled, phase III trials (studies A and B) to determine the proportion of patients with migraine achieving pain-free status 2 hours after a single oral dose of study medication (almotriptan or placebo). Pain was assessed using a 4-point integer scale (0=no headache, 3=severe headache), and recorded in a patient self-assessment booklet. Results.,The proportion of patients pain-free at 2 hours after study medication was significantly greater with almotriptan 6.25 mg (both studies P,.002) and almotriptan 12.5 mg (both studies P,.001) than with placebo. In study A, 11.6% of patients taking almotriptan 12.5 mg versus 2.5% of patients receiving placebo were pain-free at 1 hour (P=.016). At 1.5 hours, 26.8% of patients taking almotriptan 12.5 mg versus 8.8% receiving placebo (P=.001) were pain-free, and at 2 hours, 38.4% on almotriptan versus 11.3% on placebo were pain-free (P<.001). In study B, 23.8% of patients taking almotriptan 12.5 mg were free from pain at 1.5 hours versus 10.2% receiving placebo (P<.001). At 2 hours, 39.2% taking almotriptan 12.5 mg versus 15.3% receiving placebo were pain-free (P<.001). Increases in pain-free status with almotriptan generally occurred in a dose-dependent manner. Conclusion.,Compared with placebo, almotriptan 12.5 mg significantly increases the proportion of patients who are pain-free by as early as 1 hour, and consistently by 1.5 hours, after a single dose. [source]

    Impact of Chest Pain on Cost of Migraine Treatment With Almotriptan and Sumatriptan

    HEADACHE, Issue 2002
    Joseph T. Wang MS
    Chest-related symptoms occur with all triptans; up to 41% of patients with migraine who receive sumatriptan experience chest symptoms, and 10% of patients discontinue treatment. Thus, the cost of chest pain-related care was estimated in migraineurs receiving almotriptan 12.5 mg versus sumatriptan 50 mg. A population-based, retrospective cohort study used data to quantify the incidence and costs of chest pain-related diagnoses and procedures. An economic model was constructed to estimate annual cost savings per 1000 patients receiving almotriptan versus sumatriptan based on the reported rates of chest pain. Annual direct medical cost avoided was calculated for a hypothetical health plan covering 1 million lives. Among a cohort of 1390 patients, the incidence of chest pain-related diagnoses increased significantly by 43.6% with sumatriptan (P=.003). Aggregate costs for chest pain-related diagnoses and procedures increased from $22 713 to $30 234. Payments for inpatient hospital services, costs for primary care visits, and costs for outpatient hospital visits increased by over 100%, 53.1%, and 14.4%, respectively. The model predicted $11 215 in direct medical cost savings annually per 1000 patients treated with almotriptan versus sumatriptan. Annual direct medical costs avoided totaled $194 358, and when applied to recent estimates of 86 million lives currently covered by almotriptan treatment, translates into an annual cost savings of just under $17 million for chest pain and associated care. Thus, using almotriptan in place of sumatriptan will likely reduce the cost of chest pain-related care. [source]

    The Relationship between Patients' Perception of Care and Measures of Hospital Quality and Safety

    HEALTH SERVICES RESEARCH, Issue 4 2010
    Thomas Isaac
    Background. The extent to which patient experiences with hospital care are related to other measures of hospital quality and safety is unknown. Methods. We examined the relationship between Hospital Consumer Assessment of Healthcare Providers and Systems scores and technical measures of quality and safety using service-line specific data in 927 hospitals. We used data from the Hospital Quality Alliance to assess technical performance in medical and surgical processes of care and calculated Patient Safety Indicators to measure medical and surgical complication rates. Results. The overall rating of the hospital and willingness to recommend the hospital had strong relationships with technical performance in all medical conditions and surgical care (correlation coefficients ranging from 0.15 to 0.63; p<.05 for all). Better patient experiences for each measure domain were associated with lower decubitus ulcer rates (correlations ,0.17 to ,0.35; p<.05 for all), and for at least some domains with each of the other assessed complications, such as infections due to medical care. Conclusions. Patient experiences of care were related to measures of technical quality of care, supporting their validity as summary measures of hospital quality. Further study may elucidate implications of these relationships for improving hospital care. [source]

    Religious Involvement and the Use of Mental Health Care

    HEALTH SERVICES RESEARCH, Issue 2 2006
    Katherine M. Harris
    Objectives. To examine the association between religious involvement and mental health care use by adults age 18 or older with mental health problems. Methods. We used data from the 2001,2003 National Surveys on Drug Use and Health. We defined two subgroups with moderate (n=49,902) and serious mental or emotional distress (n=14,548). For each subgroup, we estimated a series of bivariate probit models of past year use of outpatient care and prescription medications using indicators of the frequency of religious service attendance and two measures of the strength and influence of religious beliefs as independent variables. Covariates included common Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, disorders symptoms, substance use and related disorders, self-rated health status, and sociodemographic characteristics. Results. Among those with moderate distress, we found some evidence of a positive relationship between religious service attendance and outpatient mental health care use and of a negative relationship between the importance of religious beliefs and outpatient use. Among those with serious distress, use of outpatient care and medication was more strongly associated with service attendance and with the importance of religious beliefs. By contrast, we found a negative association between outpatient use and the influence of religious beliefs on decisions. Conclusion. The positive relationship between religious service participation and service use for those with serious distress suggests that policy initiatives aimed at increasing the timely and appropriate use of mental health care may be able to build upon structures and referral processes that currently exist in many religious organizations. [source]

    Embedding employee involvement and participation at work

    HUMAN RESOURCE MANAGEMENT JOURNAL, Issue 3 2006
    Annette Cox
    Most quantitative studies analysing the nature and impact of employee involvement and participation (EIP) have used data that differentiate between its absence and presence. However, the application of EIP practices varies substantially, and impact may depend on how embedded EIP is at workplace level. Developing the concept of ,embeddedness' as a combination of measures of the breadth and depth of EIP practices, we use WERS98 to examine the impact of EIP on employee perceptions. Our results show support for propositions that greater breadth and depth of EIP practices are associated with higher levels of organisational commitment and job satisfaction. [source]

    Effects of sample and grid size on the accuracy and stability of regression-based snow interpolation methods

    HYDROLOGICAL PROCESSES, Issue 14 2010
    J. Ignacio López Moreno
    Abstract This work analyses the responses of four regression-based interpolation methods for predicting snowpack distribution to changes in the number of data points (sample size) and resolution of the employed digital elevation model (DEM). For this purpose, we used data obtained from intensive and random sampling of snow depth (991 measurements) in a small catchment (6 km2) in the Pyrenees, Spain. Linear regression, classification trees, generalized additive models (GAMs), and a recent method based on a correction made by applying tree classification to GAM residuals were used to calculate snow-depth distribution based on terrain characteristics under different combinations of sample size and DEM spatial resolution (grid size). The application of a tree classification to GAM residuals yielded the highest accuracy scores and the most stable models. The other tested methods yielded scores with slightly lower accuracy and varying levels of robustness under different conditions of grid and sample size. The accuracy of the model predictions declined with decreasing resolution of DEMs and sample size; however, the sensitivities of the models to the number of data points showed threshold values, which has implications (when planning fieldwork) for optimizing the relation between the effort expended in gathering data and the quality of the results. Copyright © 2009 John Wiley & Sons, Ltd. [source]